Vikings vs. Jacksonville: Three and out

The Vikings are only three days away from opening the regular season with a roster so young they might be carded at the door of Mall of America Field. But wait, there's more. Here's a trio of other things you should know: 1 Percy Harvin will be used sparingly on special teams for the foreseeable future.

On the depth chart, Harvin is listed as the Vikings' No. 1 kick returner. Right now, that's a half-truth.

With running back Adrian Peterson figured to be limited at best Sunday -- and for all of September, really -- and with receiver Jerome Simpson suspended for the first three games, Harvin's importance to the offense cannot be overstated. That means Vikings coach Leslie Frazier will take few if any risks with Harvin in the return game at the start of the season.

Does that mean Harvin will be relieved of return duties altogether?

"Not necessarily," Frazier said. "We want to still make sure that we're still utilizing all of his gifts."

Harvin's gifts have been seen plenty on special teams. Don't forget, he returned last season's opening kickoff 103 yards for a touchdown in San Diego.

But just how will the Vikings pick their spots for turning Harvin loose? As Frazier said, "A lot of it is how the game is going."

Plan B on kick returns: Marcus Sherels. But the third-year cornerback still is working back from a sprained ankle suffered two weeks ago and was limited in practice Wednesday. So Plan C would either be rookie Josh Robinson or recently acquired cornerback A.J. Jefferson.

It's also worth noting that in 2011, Jacksonville forced touchbacks on 39 of its 65 kickoffs, which could limit Harvin's involvement even further.

2 Mistral Raymond soon will be the starting safety alongside rookie Harrison Smith -- for the long haul.

If Raymond isn't given the starting nod Sunday, he'll have it before long. The Vikings have planned all offseason to move Jamarca Sanford into a role that better fits him. That means he'll be considered a reliable reserve in the secondary and a valuable contributor to special teams.

Raymond, meanwhile, is on the ascent and seemed poised to take over a starting safety spot a few weeks ago. But then he was struck by back spasms during warmups of the third preseason game. So the coaches want to make sure his back troubles aren't lingering before clearing him for a starting role.

"Just telling him to be patient and let us take a look at some things these next couple of days," Frazier said. "We'll make a decision as the week goes on. We have confidence in both of them, and we'll make the right decision."

If Raymond wins the job this week, the Vikings will enter the season with a pair of safeties with little or no NFL game experience, needing Smith and Raymond to develop quickly.

3 Justin Blackmon's hands have Mike Mularkey's attention.

Blackmon should be a focal point of Jacksonville's passing attack right out of the gates. The Jaguars rookie receiver had 10 catches for 136 yards during the preseason and quickly is developing rapport with quarterback Blaine Gabbert.

Don't forget, before drafting Matt Kalil, the Vikings took a long, hard look at Blackmon, impressed with his hands and ability to make catches in traffic.